Hi there. A few months ago I got penile papules and they were a bit annoying when they first appeared. For some reason it felt itchy. Then the papules got smaller. Today there is some part of my penis that is red and I'm experiencing some pain on my penis for two days or so. The papules are also red and there is bad smell coming from them. Are these symptoms related in some way? Is this natural or there is a problem?
I think that you mistook a problem for penile papules or that you had multiple things come about the same time. Red and itchy generally points to either a fungal infection or a bacterial infection. The bad smell is consistent with this as well. Pain tells me you've been ignoring this way too long. I can't tell you what you actually have because I haven't seen it and I can't do tests like a doctor can.
Let's first assume that it is a fungal infection. Go to the drug store and get an anti-fungal medication. The layman's term for this is something to cure Jock Itch. Follow the directions carefully and use it for several days. If it is a fungal infection, you'll quickly notice an improvement. If so, complete the entire sequence in the directions. The symptoms will disappear before the fungus is completely killed, but you have to continue the treatment as directed to get rid of it. Otherwise, it will just come back.
If it doesn't improve or doesn't completely go away, then likely you have an bacterial infection or got a bacterial infection in addition to the fungal infection. Use an antibiotic ointment twice a day for a few days and see if there is any improvement. If not, you might have something that is resistant to treatment. You will then need to go to your doctor who will give you something stronger and more specific to what you actually have.